Problem of excessive element distortion in ALE adaptive meshing
Problem of excessive element distortion in ALE adaptive meshing
(OP)
Hi
My friends
In my model, which is suction of a gel to a pipette, the step visco fails to converge and yields the error of "too many attempts "at the beginning or middle of the procedure which is likely due to "excessive element distortion".
Tricks like altering *CONTROLS will only delay the inevitable as a friend truly said.
As much as I have perceived, Dynamic Explicit is the a good way in combination with ALE adaptive meshing to tackle element distortion problem. It is clear that it helps the process to go further but it still fails due to distortion!!! and gives the following error:
" There are a total of 2 excessively distorted elements The elements contained in element set ErrElemExcessDistortion-Step1 have distorted excessively."
How do you recommend me to change and adjust the Adaptive meshing parameters like frequency, number of sweeps and if it helps to use adaptive mesh controls to get rid of this problem? I tried various values for these frequency and number of sweeps but the problem still exists with a little temporal shift.
I am not very familiar with this topic and Abaqus manual was somehow vague in this regard.
Is ALE adaptive ineffective in solving my case and I have to try another way?
Links to photos that may help to have a schematic imagination of the model:
1- http://fil es.enginee ring.com/g etfile.asp x?folder=b 701fb87-7f 6e-4d16-97 00-63d1623 e7cec& file=1.JPG
2- http://fil es.enginee ring.com/g etfile.asp x?folder=5 5bd768e-91 cc-40f4-99 49-34b896f 2b9c2& file=2.JPG
Many thanks in advance
My friends
In my model, which is suction of a gel to a pipette, the step visco fails to converge and yields the error of "too many attempts "at the beginning or middle of the procedure which is likely due to "excessive element distortion".
Tricks like altering *CONTROLS will only delay the inevitable as a friend truly said.
As much as I have perceived, Dynamic Explicit is the a good way in combination with ALE adaptive meshing to tackle element distortion problem. It is clear that it helps the process to go further but it still fails due to distortion!!! and gives the following error:
" There are a total of 2 excessively distorted elements The elements contained in element set ErrElemExcessDistortion-Step1 have distorted excessively."
How do you recommend me to change and adjust the Adaptive meshing parameters like frequency, number of sweeps and if it helps to use adaptive mesh controls to get rid of this problem? I tried various values for these frequency and number of sweeps but the problem still exists with a little temporal shift.
I am not very familiar with this topic and Abaqus manual was somehow vague in this regard.
Is ALE adaptive ineffective in solving my case and I have to try another way?
Links to photos that may help to have a schematic imagination of the model:
1- http://fil
2- http://fil
Many thanks in advance





RE: Problem of excessive element distortion in ALE adaptive meshing
Forever Young.....
RE: Problem of excessive element distortion in ALE adaptive meshing
RE: Problem of excessive element distortion in ALE adaptive meshing
Forever Young.....
RE: Problem of excessive element distortion in ALE adaptive meshing
For large deformations you should try to design the mesh such that the element distortion is minimized.
Also, you should try to reduce the frequency for ALE.
RE: Problem of excessive element distortion in ALE adaptive meshing
Hi!
Dear williwang
The method which you mentioned(Mesh to mesh solution mapping )is,as far as I know,not a very time-friendly one,besides I am not familiar with that process.I have put it aside as the last card when all the other otions failed to answer.I am still experimenting ALE and will let you know my discoveries!
RE: Problem of excessive element distortion in ALE adaptive meshing
Dear Xerf
For the 1st point,I am of the opinion that your model should answer regardless of the mesh type you choose,
yeah;using tri elements or a coarser mesh help but why shouldn't I be able to elicit answer with quad for example?
So I guess that the fundamental problem lies somewhere else.
And for the 2nd,
I am not very sure now but as I highly increase the frequency it goes further without any error! But as the solution time was very long I am still not sure about the results. I will let you know the outcome.
Regards
RE: Problem of excessive element distortion in ALE adaptive meshing
If I am not wrong, for the FREQUENCY parameter one specify the number of time increments after which the adaptive meshing is called. Therefore, by decreasing its value, the adaptive meshing will be applied more often.
Best.
RE: Problem of excessive element distortion in ALE adaptive meshing
Your idea initiated some doubt,I will check this.
Thanks dear,
Bests
RE: Problem of excessive element distortion in ALE adaptive meshing
As much as I have understood, increasing the frequency will request the adaptive meshing procedure to occur more often and therefore distortion will be procrastinated.
But in my case I think that distortion is inevitable since the loading is introduced to be instantaneous which means a huge load applied in a very short time interval and therefore an impact which makes the elements to distort.
As I have to introduce the load instantaneously and not as a ramp , I have to find a cure for this case.
Regards
RE: Problem of excessive element distortion in ALE adaptive meshing
Thank you all my friends for your ideas and contributions,
Regards